Sort of hard to carry a cannon into a shopping mall or movie theater without giving everyone plenty of warning. A cannon, however, doesn’t necessarily meet the definition of an arming weapon. By many historical definitions, it should be something easy to carry and incapable of inflicting area damage to random targets.
If you’ll notice, the quotes I posted don’t say anything about portability, and marque and reprisal on the high seas with ships wouldn’t work with only muskets.